Spark plug gapping tool



Feb; 3, 1959 w. w. WEISBEICKER IflAL 2,871,741

SPARK PLUG GAPPING TOOL Filed Sept. 28. 1956 INVHVTORS WALTER wwasaazmesz BY aeuawwemsecnz AT ORNEY-5 United dtatcs Patent SPARK PLUG GAPPING TODL Walter W. Weisbecker and Irene M. Weisbecker, Rantoul, Ill.

' Application September 28, 1956, Serial No. 612,637

1 Claim. (Cl. 81-15) This invention relates to an improved spark plug gapping tool of the pliers and rotary gauge type.

The primary object of the invention is to provide a more practical and efficient tool of this kind which can be applied and operated more quickly, is simple in construction, and is composed of a small number of simple and easily assembled parts.

Another object of the invention is to provide a tool of the character indicated, which can be made in wellfinished, rugged, and serviceable forms at relatively low cost, is easily used, and is highly satisfatory for the purpose intended.

These together with other objects and advantages which will become apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout the several views, and in which:

Figure 1 is a perspective view of a tool of the invention, shown applied to a spark plug shown in phantom lines;

Figure 2 is an enlarged fragmentary side elevational view of the tool;

Figure 3 is a fragmentary top plan view of Figure 1 the spark plug being shown in phantom lines; and

Figure 4 is a fragmentary vertical transverse sectional view taken substantially on line 44 of Figure 2, an associated spark plug being shown in phantom lines.

Referring to the drawings in detail, the illustrated tool, indicated generally at 10, is usable for adjusting the gap between the center electrode 12 and the radial electrode 14 of a spark plug, indicated generally at 16, the radial electrode 14 being bendable toward and away from the upper end of the center electrode 12.

The gapping tool comprises a pair of crossed levers and 22 pivoted on a pivot pin 24 extending therethrough, and having handle portions 26 and 28, respectively, and upper and lower jaws 30 and 32, respectively.

The upper jaw 30 includes a nose 35 which terminates at is forward end in a longitudinally extending fiat lug 34 whose underside is flush with the flat straight underside 33 of the nose 35. The lower jaw 32 lacks a nose, like the nose 35, whose place is taken by an elongated laterally angled arm 36 having a forward end 37 in which is a vertical bore 38 through which extends a vertical headed pin 40, rotatably mounting on the upper side of the arm 36 an electrode gap gauge, indicated generally at 42.

The gauge 42 comprises a disc 44 having thereon circumferentially spaced radial gauge lugs 46 of different thicknesses. On the upper surface of the disc 44 are indicia 48 identifying the dilferent gauge lugs. The gauge lugs 46 are adapted to be selectively positioned beneath and in spaced relation below the upper jaw lug 34 by rotating the disc 44.

As shown in Figure 4, a spark plug 16 is gapped by positioning the center electrode 12 under the upper jaw lug 30, with a selected gauge lug 46 between the center electrode 12 and the radial electrode 14. Thereupon the handle portions 26 and 28 are compressed toward each other. If the gap between the electrodes corresponds to the thickness of the gauge lug 46 used, no change in the gap results, but if the gap is larger than the thickness of the gauge lug 46 used, the gap between the electrodes will be closed to the extent necessary to provide a gap corresponding to the thickness of the gap lug used, by the bending pressure of the upper lug 34 on the radial electrode 14.

If the gap between the electrodes 12 and 14 is too small, a thinner gauge lug 46 is placed between the electrodes and the tool twisted to increase the gap, whereafter the above described procedure is used to exactly gap the electrodes.

The foregoing is considered as illustrative only of the principles of the invention. Since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, as fall within the scope of the appended claims.

What is claimed as new is as follows:

A tool. for adjusting the air gap between the outer and central electrodes of a spark plug, said tool comprising a pair of opposing, complemental jaws having crossed handles pivotally connected together for moving the jaws toward and away from each other, one jaw having a forwardly projecting lug constituting an axial prolongation thereof, said lug having an underface disposed in a plane that contains the pivot axis of the handles, the other jaw terminating inwardly of said one jaw and having an extension arm extending laterally outwardly and projecting forwardly therefrom, said arm terminating in a free outer end disposed substantially in lateral alignment with said lug, a disc rotatably mounted on the free end of the arm and rotatable about an axis perpendicular to the pivot axis of the handles, said lug having a side facing the arm and disposed in a plane perpendicular to and tangentially disposed relative to an extension of the curvilinear plane in which the periphery of the disc lies, said disc having integral gauging .lugs of varying thickness extending radially from the periphery thereof and disposedv in circumferentially spaced fashion on the periphery, said gauging lugs being of a length substantially equal to the width of said lug and each gauging lug having a face adapted to confront said underface of said lug with each gauging lug being adapted to selectively seat on a central electrode and having it face bearing under an outer electrode and with the lug engaging at its underface on the outer electrode and clampingly cooperating with the selected gauging lug to bend the outer electrode relative to the central electrode.

References Cited in the file of this patent UNITED STATES PATENTS 1,384,209 OToole July 1.2, 1921 2,492,380 Duma Dec. 27, 1949 2,645,142 Schwenzfeier July 14, 1953 2,670,643 Clark Mar. 2, 1954 FOREIGN PATENTS 125,449 Australia Sept. 12, 1947 

